Some symbols of the greasers are the long hair, t-shirts, and souped-up cars, and symbols of the Socs are muscle cars.

In Ponyboy’s world, there are two gangs. They are not named street gangs, but rather nicknames for social classes. The lower class kids are called greasers, and the rich kids are called Socs. Ponyboy explains that not all greasers are the same.

Greasers are almost like hoods; we steal things and drive old souped-up cars and hold up gas stations and have a gang fight once in a while. (ch 1)

Pony points out that he is not a hoodlum. His older brother tries to keep him out of trouble, and would kill him if he had a run in with the law.

I only mean that most greasers do things like that, just like we wear our hair long and dress in blue jeans and T-shirts, or leave our shirttails out and wear leather jackets and tennis shoes or boots. (ch 1)

The Socs are the rich kids, and “they’ve got all the breaks.” They live on the other side, and have a real sense of entitlement.

The girls who were bright-eyed and had their dresses a decent length and … looked at us like we were dirt-gave us the same kind of look that the Socs did when they came by in their Mustangs and Corvairs and yelled "Grease!" at us. (ch 1)

Despite the fact that the Socs are wealthy, they can be just as violent as any greaser. In fact, it is their jumping Johnny that causes Pony and Johnny to get into the fight with Bob and his friends that results in Johnny killing Bob.